One embodiment of a shock apparatus comprises a plurality of impact objects spatially ordered according to decreasing mass along a substantially linear path; a guide to guide movement of the impact objects along the path; and a plurality of spacers, one spacer between each adjacent pair of impact objects in the spatial order. The guide and spacers enable a plurality of temporally ordered impacts involving the plurality of impact objects. In one embodiment, at least one of the impact objects comprises an impact portion positioned at a point where the impact object impacts at least one other impact object; and the properties of the impact portion are selectable to affect the magnitude and duration of a shock acceleration pulse experienced by the at least one impact object.